The state legislature in Minnesota is looking at a bill that would restrict phosphorus levels in automatic-dishwashing detergents. Supporters say it would reduce harmful algae blooms in lakes and streams. If the bill passes, it would be the first state to make such restrictions. The Great Lakes Radio Consortium’s Christina Shockley reports:
Transcript
The state legislature in Minnesota is looking at a bill that would restrict phosphorus levels in
automatic-dishwashing detergents. Supporters say it would reduce harmful algae blooms in lakes
and streams. If the bill passes, it would be the first state to make such restrictions. The Great
Lakes Radio Consortium’s Christina Shockley reports:
Phosphorus in detergents helps to clean dishes, but when the mineral ends up in lakes and
streams, it promotes algae blooms. Large algae blooms can kill fish and restrict sunlight to
bottom-rooting plants. In the 1970s, phosphorus was restricted in other types of detergents.
David Mulla is a professor in the soil, water, and climate department at the University of
Minnesota. He says that legislation did make a difference.
“We had a very large reduction in the amount of phosphorus that was being emitted to our waste
water treatment plants as a result.”
However, Mulla says dishwashing detergents are not one of the primary sources of phosphorus in
lakes and streams today. Detergent manufacturers say if they don’t use phosphorus, their
detergents might not meet some health standards. They also say a reduction won’t have any
environmental benefits. The bill is currently being discussed in the state legislature.
For the Great Lakes Radio Consortium, I’m Christina Shockley.